1. Field of the Invention
The present invention relates to a wide-angle zoom lens system having an angle-of-view of approximately 100° at the short focal length extremity.
2. Description of the Prior Art
Zoom lens systems whose purpose is to achieve a wider angle-of-view through a three-lens-group arrangement, i.e., a lens group having a negative power (hereinafter, a negative lens group), and a lens group having a positive power (hereinafter, a positive lens group) and another positive lens group in this order from the object, are proposed in Japanese Unexamined Patent Publication (JUPP) Nos. Hei-4-70706, U.S. Patent (hereinafter, U.S. Pat. No. 6,246,529, and U.S. Pat. No. 6,327,098. However, the angle-of-view at the short focal length extremity in the zoom lens system of JUPP No. Hei-4-70706 is about 61.6°, and the zoom lens systems of U.S. Pat. No. 6,246,529 and U.S. Pat. No. 6,327,098 are 95.6°. Accordingly, the wider angle-of-view at the short focal length extremity has not been sufficiently achieved, and no consideration has substantially be taken to miniaturization on the lens diameter which becomes larger as an increase of the angle-of-view.